The invention relates to a spindle drive for measuring devices and coordinate measuring centers, comprising a horizontally mounted drive spindle which is engaged without play with a nut while the nut is connected to a slide which is displaceable in the lengthwise direction by the spindle drive, with either a driven spindle engaging a fixed nut or, in kinematic reversal, a driven nut engaging a fixed spindle, and with the slide being firmly connected to a measuring carriage or the like movable below the drive spindle, through a screw connection and a bracket arm of a supporting structure, which arm roofs both the drive spindle and the slide.
With prior art spindle drives, a lengthwise displacement of a measuring carriage is obtained while turning the drive spindle in the fixed nut. This transformation of a rotary motion into a lengthwise or advance motion usually fails to be effected without a deformation and displacement of the measuring carriage from the ideal position of the parts to be driven. Already slight deformations result in a change in the position of the already aligned measuring carriage.
Non-circularity of the drive spindle or the small-size nut or even slight imperfections of the thread of the spindle or nut cause misalignments in the position of the measuring carriage and lead to measuring errors.
Upon a slight angular correction of the measuring carriage, which is unavoidable in the final adjustment, a subsequent alignment of the drive spindle center is always necessary.